2006/11/04 by Ji-Woo Lee, Lee, Ji-Woo, Shailesh Chandrasekharan +3
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Quantum many-body systems #Quantum, superfluid, helium dynamics #Statistical Mechanics (cond-mat.stat-mech) #Superconductivity (cond-mat.supr-con) #cond-mat.stat-mech #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0611109
6 pages, 6 figures
arxiv created 2006/11/04 · openalex publication_date 2006/11/04 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the effect of disorder on hardcore bosons in two dimensions at the SU(2) symmetric ``Heisenberg point''. We obtain our results with quantum Monte Carlo simulations using the directed loop algorithm. In the absence of disorder, the system has no long-range order at finite temperature due to the enhanced symmetry. However, the introduction of a disordered potential, uniformly distributed from -D to D, induces a finite-temperature superfluid phase. In particular the diagonal correlation length ξdecreases but the superfluid order-parameter correlation function becomes a power-law. A non-monotonic finite-size behavior is noted and explained as arising due to ξ. We provide evidence that at long distances the effects of a weak disordered potential can be mimicked by an effective uniform potential with a root-mean-square value: mueff = D/sqrt3. For strong disorder, the system becomes a Bose glass insulator.